A new survey finds support is growing in the United States for same-sex marriage, which was legalized by three states in last month's national election.

A Quinnipiac University poll released Wednesday shows 48 percent of voters support same-sex marriage, and that 46 percent oppose the practice. That is a reversal of the 55 percent to 36 percent opposition from a Quinnipiac poll in 2008.

In the November 6 election, voters in Maryland, Maine and Washington state supported measures that legalize same-sex marriage.

The poll also found 51 percent of Americans believe marijuana should be legalized.

Fifty-nine percent of men supported legalizing the drug, compared with 52 percent of women.

In last month's election, voters in Colorado and Washington state approved the recreational use of marijuana. They became the first U.S. states to do so even though use of the drug is illegal under federal law.

Eighteen states and Washington, D.C. have enacted laws to legalize marijuana for medicinal purposes.